Generic hand-guided machines for ground compaction are used in situations in which only a restricted working space is available, only small areas require compacting, and/or selective compacting measures are desired. This is, for example, the case with indoor or small construction sites and in trench and canal engineering. Typically, these hand-guided ground compacting machines comprise a driving engine which is arranged on a machine frame and which provides the driving energy required during working operation of the ground compacting machine. Thus, the machine frame is that component of the ground compacting machine on which the driving engine and possible further components, such as, in particular, a guide bar, for example, are attached. The machine frame is, thus, substantially a single-piece or multi-piece supporting structure, particularly, also for the driving engine. Specifically, the engine drives a device for ground compaction, which can be a base or foot of a vibration tamper or a ground plate of a vibratory plate, for example. A suitable drive transmission operatively connects the driving engine to the ground compaction device such that the ground compaction device executes a compacting motion, particularly towards the ground subsurface. For this purpose, it is known in the prior art to arrange said drive transmission as a crank drive for vibration tampers or as a belt drive for an exciter unit mounted on a vibratory plate, for example. Further, a guide bar is provided by means of which the operator guides the ground compacting machine over a soil subsurface to be compacted during operation. In order to, as far as possible, reduce or even eliminate the transmission of vibration to the operator and to counteract undesired side effects on the operator, such as, for example, the HAV syndrome, said guide bar is preferably arranged so as to be vibration-cushioned in relation to the machine frame. The measures used for establishing such vibration attenuation are known per se. For example, suitable rubber mountings or similar vibration damping devices can be used for this purpose. The main property of the damping elements used is that vibration incited therein by the machine frame are either completely eliminated in the damping element or are damped and then transferred to the other side with an attenuated intensity. Generic ground compacting machines are disclosed in the prior art, for example, in DE 10 2009 017 209 B4, DE 10 2010 046 820 A1 and DE 10 2010 047 943 A1 for vibration tampers, as type designations BW 55 E and BW 65 H for vibratory rollers manufactured by the Applicant, and in DE 10 2010 008 309 A1 for a vibratory plate. These specifications are likewise incorporated herein by reference with regard to their construction and the manner of operation of generic ground compacting machines.
The driving engines used for generic hand-guided ground compacting machines are typically diesel engines two-stroke and four-stroke internal combustion engines powered by gasoline or diesel fuel. However, these driving engines are disadvantageous inter alia in that they have comparatively high emission levels, especially with respect to the concentration of carbon monoxide in the exhaust fumes. An additional problem, particularly related to diesel driven engines, is the frequent generation of very high amounts of soot. This problem is particularly conspicuous when a hand-guided ground compacting machine is used indoor or under very restricted spatial conditions, as, for example, in trench engineering. A further problem arises from the fact that the operator, who manually guides the ground compacting machine, will constantly remain in the immediate vicinity of the source of the exhaust fumes. As an alternative, hand-guided ground compacting machines are further known that are operated on electrical energy, such as, for example, DE 10 2011 105 899.4 owned by the Applicant. Especially, the accumulators necessary, therefore, are, however, still relatively expensive, and the operating periods thus attainable are comparatively short. Another basic objective to be regarded when developing hand-guided ground compacting machines, consists in that safe and reliable operation should be made possible in spite of the vibration naturally occurring under working conditions.